Coolant supply and exhaust discharge means for inboard-outboard drives



May 4, 1965 E. c. KIEKHAEFER 3,181,495

COOLANT SUPPLY AND EXHAUST DISCHARGE MEANS FOR INBOABD-OUTBOARD DRIVESFiled Jan. '7, 1963 2 Sheets-Sheet 1 s L a INVENTOR. [Laura C.)fisnnntaa jadrus F sfdrlfe Arr-m ne L:

y 4, 1965 E. c. KIEKHAEFER 3,181,495

COOLANT SUPPLY AND EXHAUST DISCHARGE MEANS FDR INBOARD-QUTBOARD DRIVESFiled Jan. '7, 1963 2 Sheets-Sheet 2 1| Z 6 ik m 65 i 21 16 I: 30 7- 32/ I a 2a INVENTOR. [0051: C Mummers! 3 BY shaft 12 bendscorrespondingly at the joint to accommodate steering movements of theunit. Steering control of the unit is provided by remote control meanswhich pivots the steering arm 34 secured on swivel shaft.

element 32.

According to this inventiomthe stern drive unit having steering andtiltaxes ahead of the vertical drive shaft of the unit is adapted toreceive the exhaust products from the inboard engine 11 for dischargebeneath the water surface and the engine cooling water is picked up bythe drive unit and conducted to the engine.

The exhaust products resulting from engine operation are discharged fromengine 11 through the exhaust pipe 35 which extends rearwardly anddownwardly from the engine. Exhaust pipe 35 is disposed to the sideofthe horizontal drive shaft 12 and the flexible conduit 36 is connectedthereto and extends downwardly and around the drive shaft and enginecoupling element 27. Conduit 36 passes through opening 37 in the lowerportion of inner transom plate 17 and into transom opening 19 forconnection to the forward projection of tubular connector 38 which isaligned with opening 37 and formed integrally with the outer transomplate 18 about an axis in the vertical plane containing the axis ofdrive shaft 12.

The dirigible and tiltable stern drive unit 1 is provided with an inlet39 for engine exhaust products in the lower portion of bell housing 36which is generally in alignment with and of the same size as therearward projection of transom plate connector 38. An expandable bellowsconduit 40 extends through the gimbal ring member 29 and connects thefixed transom plate connector 38 and movable stern. drive inlet 39providing passage for the exhaust products from engine 11 to theinterior of the stern drive unit without interference from or tosteering and tilt movements of the'drive unit.

In the interior of the stern drive unit 1, the exhaust products movedownwardly and are directed into the propeller hub passages 41 fordischarge under water from the discharge opening 42 rearwardly of thepropeller 4.

The water for engine cooling is picked up through a series of verticallyspaced openings 43 provided on each side of the stern drive unit 1beneath the anti-cavitation plate 44. The openings 43 communicate with avertically extending internal cored passage 45 which conducts the waterto the impeller pump 46 driven by vertical drive shaft 6. Pump 46 forcesthe coolant through the upwardly extending tubular member 47 intochamber 48 which is disposed rearwardly of and adjacent to the gearchamber 15 to provide for cooling .of the latter chamber.

From cooling chamber 48, the cooling water flows through the tranversepassage 49 into the longitudinal passage 50 extending along the side ofthe gear chamber 15. Passage 50 terminates with a forwardly extendingtubular projection 51 opening within the stern drive bell housing 30generally between horizontal drive shaft 12 and the exhaust inlet 39 andto the right of the vertical plane through the axis of shaft 12 asviewed in FIG. 5.

A flexible conduit 52 extends through gimbal ring member 29 and spansthe distance between the fitting 53 threaded into projection 51 movablewith the dirigible and tiltable stern drive unit 1 and the tubularfitting 54 secured within the generally fixed outer transom plate 18above horizontal drive shaft 12 and .on the opposite side of thevertical plane through the axis of shaft 12 from projection 51. Conduit52 is clamped onto fitting 53 and extends forwardly and around thebellows connector 55 extending between the stern drive bell housing 30and the outer transom plate 18 and enclosing the horizontal drive shaft12 at the double universal joint 16. The end portion-of conduit 52adjacent to transom plate 18 generally parallels the plate and isclamped to angular fitting portion 56 which opens generally normal to aradial line through the axis of the horizontal drive shaft so thatconduit 52 spans the distance from the movable stern drive unitrelatively smoothly and is substantially free from kinks. Sincethe'fittings 53 and 54 are disposed generally equidistantly andoppositely with respect to the vertical and horizontal planes throughthe axis of drive shaft 12, conduit 52 will not be unduly stressedduring steering and tilt movements of the propulsion unit.

The fitting 54 carries the coolant through the outer transom plate 18and is mounted within the outer transom plate projection 57 whichextends inboard through the opening 53 in the inner transom plate 17.The fitting 54 is disposedin a'frusto-conical rubber bushing 59 which Iis adapted to be wedged into the tapered opening-60 through projection57 to securely hold the fitting and prevent water from leaking throughopening 60 into the interior of the Watercraft. An elliptical plate 61having an opening 62 to pass over fitting 54 is adapted for securementto the forward face of projection 57 to compress the bushing 59 intointimate contact with the fitting and the wall forming opening 60 in theprojection.

Forwardly of the transom plate assembly, fitting 54 includes an angularportion 63 which extends upwardly and to the right as viewed in FIG. 4to eliminate undue kinking in the flexible conduit 64 clamped to fittingportion 63. Conduit 64 extends forwardly and around the side of engine11 for connection to the engine pump 65 which circulates the coolantthrough appropriate engine passages, not shown. After the coolant hasserved its purpose within engine 11, the heated 'water is dischargedinto the engine exhaust pipe 35 through conduit 66 connecting the pipewith the engine outlet 67. The discharged coolant thus serves to coolthe engine exhaust products flowing through the exhaust pipe and passesthrough the exhaust system for discharge from the stern drive unit withthe exhaust products.

With the structure of'this invention wherein the exhaust products passthrough the stern drive unit for underwater discharge a more quietengine operation results without need for a separate mufiier to take upspace in the watercraft. Provision for coolant pickup in the stern driveunit eliminates the need for a separate pickup on the watercraft wheresuch would not only be vulnerable to damage but also would impose asubstantial drag upon the progress of the watercraft. With a coolantwater pickup in the sterndrive unit, the coolant also becomesconveniently available to cool the upper gear case in the unit.

Various modes of carrying out the invention are contemplated as beingwithin the scope of the following claims particularly'pointing out anddistinctly claiming the subject matter which is regarded as theinvention.

I claim:

1. In an inboard-outboard drive for watercraft, an engine disposedinboard of the Watercraft, a propulsion unit disposed outboard of thewatercraft and dirigibly and pendently supported therefrom for steeringmovement on a generally vertical axis and for tilt movement on agenerally horizontal transverse axis substantially intersecting saidsteering axis, a substantially vertical drive shaft in said propulsionunit rearward from said steering axis, drive means interconnecting saidengine and said propulsion unit drive shaft, mounting means for saidpropulsion unit secured to the transom of the watercraft and surroundingan opening through said transom for receiving said drive means, waterpick-u means in said pro pulsion unit, a Water pump in said propulsionunit driven by said drive shaft and connected to receive water from saidpick-up means, means to conduct water from said pump through thepropulsion unit and through the transom opening and said mounting meansto said engine and including flexible conduit means adjacent said axesintersection to provide freedom for steering and tilt movements of saidpropulsion unit upon said axes.

2. In an inboard-outboard drive for watercraft, an en- 5 gine disposedinboard of the Watercraft, a propulsion unit disposed outboard of theWatercraft and dirigibly and pendently supported therefrom for steeringmovement on a generally vertical axis and for tilt movement on agenerally horizontal transverse axis substantially intersecting saidsteering axes, a substantially vertical drive shaft in said propulsionunit rearwardly of said steering axis, drive means interconnecting saidengine and said propulsion unit drive shaft, mounting means for saidpropulsion unit secured to the transom of the Watercraft and surroundingan opening through said transom for receiving said drive means, andengine exhaust passage means extending from said engine through saidtransom opening and said mounting means into and through said propulsionunit and including a flexible and expandable conduit section adjacent tosaid axes intersection to provide freedom for steering and tiltmovements of said propulsion unit upon said axes without interruption ofsaid passage means.

3. In an inboard-outboard drive for Watercraft having a transom, anengine disposed inboard of the Watercraft, a propulsion unit disposedoutboard of the Watercraft and having an anti-cavitation plate and avertical drive shaft and being dirigibly and pendently supported fromthe transom on generally vertical and transverse horizontal axesforwardly of said drive shaft, a horizontal drive shaft extendingthrougi the transom and drivingly connecting the vertical drive shaftand said engine and being adapted to accommodate movements of thepropulsion unit on said axes, mounting means for said propulsion unitsecured to said transom and surrounding an opening through the transomfor said horizontal drive shaft, pickup means for en ine cooling Waterin said propulsion unit beneath the anti-cavitation plate, outlet meanson said propulsion unit above the anti-cavitation plate andcommunicating with said cooling water pickup means, and conduit meansextending through said transom opening and said mounting means andconnecting the propulsion unit outlet means to the engine for carryingthe cooling water to the engine, said conduit means being adapted toflex in the region of said generally vertical and transverse horizontalaxes as not to interfere with the steering and tilt movements of thepropulsion unit.

4. In an inboard-outboard drive for watercraft having a transom, anengine disposed inboard of the watercraft, a propulsion unit disposedoutboard of the Watercraft and having an anti-cavitation plate and avertical drive shaft and being dirigibly and pendently supported fromthe transom on generally vertical and transverse horizontal axesforwardly of said drive shaft, a horizontal drive shaft extendingthrough the transom and drivingly connecting the vertical drive shaftand said engine and being adapted to accommodate movements of thepropulsion unit on said axes, mounting means for said propulsion unitsecured to said transom and surrounding an opening through the transomfor said horizontal drive shaft, engine exhaust discharge means in saidpropulsion unit beneath the anti-cavitation plate, inlet means on saidpropulsion unit above the anti-cavitation plate and communicating withsaid exhcust discharge means, and conduit means extending through saidtransom opening and said mounting means and connecting the propulsionunit inlet means to the engine exhaust pipe and carrying the engi eexhaust products to the propulsion unit for discharge under Water, saidconduit means being adapted to hex and expand in the region of saidgenerally vertical and transverse horizontal axes so as not to interferewith the steering and tilt movements of the propulsion unit.

5. In an inboard-outboard drive for watercraft having a transom, anengine disposed inboard of the watercraft, a propulsion unit disposedoutboard of the Watercraft and having an anti-cavitation plate and avertical drive shaft, mounting means for said propulsion unit secured tosaid transom and surrounding an opening through the transom, saidpropulsion unit being dirigibly and pendently supported by said mountingmeans on generally vertical and transverse horizontal axes forwardly of'said drive shaft, a horizontal drive shaft extending through the transomopening and drivingly connecting the vertical drive shaft and saidengine and being adapted to accommodate movements of the propulsion uniton said axes, pickup means for engine cooling Water and engine exhaustdischarge means in said propulsion unit beneath the anti-cavitationplate, cooling water outlet means on said propulsion unit above theanti-cavitation plate and communicating with said cooling Water pickupmeans, exhaust inlet means on said propulsion unit above theanti-cavitation plate and communicating with said exhaust dischargemeans, conduit means extending through the transom opening and mountingmeans and connecting the propulsion unit outlet means to the engine forcarrying cooling Water to the engine, and conduit means extendingthrough the transom opening and mounting means and connecting thepropulsion unit inlet means to the engine exhaust pipe for carrying theengine exhaust products to the propulsion unit for discharge underWater, said respective conduit means being adapted to flex in the regionof said generally vertical and transverse horizontal axes so as not tointerfere with the steering and tilt movements of the propulsion unit.

6. In an inboard-outboard drive for Watercraft having a transom, anengine disposed inboard of the Watercraft, a propulsion unit disposedoutboard of the Watercraft and having an anti-cavitation plate and avertical drive shaft, support means mounted on the transom and dirigiblyand pendently supporting the propulsion unit on generally vertical andtransverse horizontal axes forwardly of said vertical drive shaft, ahorizontal drive shaft extending through said transom and support meansand drivingly connecting the vertical drive shaft and said engine andbeing adapted to accommodate steering and tilt movements of thepropulsion unit on said axes, pickup means for engine cooling water anddischarge means for engine exhaust in said propulsion unit beneath theanti-cavitation plate, cooling water outlet means on said propulsionunit above the anti-cavitation plate and communicating with said coolingWater pickup means, exhaust inlet means on said propulsion unit abovethe anti-cavitation plate and com municating with said exhaust dischargemeans, said propulsion unit support means including through transomcooling Water passage means and exhaust passage means respectivelycommunicating with the engine, and flexible conduit respectivelyconnecting the propulsion unit cooling water outlet means to the coolingWater passage means and the propulsion unit exhaust inlet means to theexhaust passage means so as not to interfere with the steering and tiltmovements of the propulsion unit.

7. The invention of claim 6 wherein the driving connection between thehorizontal and vertical drive shafts consists of meshing gears disposedWithin a chamber in the propulsion unit and the cooling water flowingthrough the propulsion unit between the pickup means and out let meansis conducted through passage means in heat interchange relation with thegear chamber.

8. In an inboard-outboard drive for Watercraft having a transom, anengine disposed inboard of the Watercraft, a propulsion unit disposedoutboard of the Watercraft and having an anti-cavitation plate and avertical drive shaft, support means mounted on the transom, a gimbalring member pivotally supporting the propulsion unit on a generallytransverse horizontal axis to accommodate tilt movements of the unit ina generally vertical plane and being pivotally supported by the supportmeans on a generally vertical axis to accommodate steering movements ofthe member together with the propulsion unit in a generally horizontalplane, a horizontal drive shaft extending through said transom andgimbal ring member and drivingly connecting the vertical drive shaft andsaid engine and having universal coupling means to accommodate steeringand tilt movements of the propulsion unit on said axes, pickup means forengine cooling 6' Water and discharge means for engine exhaust providedin the propulsion unit beneath the anti-cavitation plate, cooling wateroutlet means on said propulsion unit above the anti-cavitation plate andcommunicating with said cooling water pickup means, exhaust inlet meanson said propulsion unit above the anti-cavitation plate andcommunicating with said exhaust discharge means, said transom supportmeans including through transom cooling water passage means and exhaustpassage means respectively communicating with the engine, and flexibleconduit extending through the gimbal ring member and connecting thepropulsion unit cooling water outlet means to the cooling water passagemeans and the propulsion unit exhaust inlet means to the exhaust passagemeans to provide for uninterrupted flow of coolant and exhaust productsrespectively and without interference to the steering and tilt movementsof the propulsion unit.

9. The invention of claim 8 wherein the driving conand the flexibleconduit connecting said inlet means and passage means is a bellowsconnector.

11. The invention of claim 8 wherein the propulsion unit cooling wateroutlet means 'opens forwardly and is 8 disposed beneath the horizontaldrive shaft and to one side of the vertical plane through the axis ofsaid shaft and the cooling water passage means in the transom supportmeans constitutes a fitting disposed above said shaft and on theopposite side of the vertical plane through the axis of said shaft fromsaid outlet means, said fitting having an outboard end portion whichopens generally normal to a radial line through the axis of thehorizontal drive shaft so that the flexible conduit connecting theoutletlmeans and fitting and extending around the horizontal drive shaftis substantially free of kinks.

12. The invention of claim 8 wherein the cooling water outlet means onthe movable propulsion unit and the cooling water passage means on thegenerally fixed transom support means'are disposed generallyequidistantly and oppositely with respect to vertical and horizontalplanes through the axis of the horizontal drive shaft so that theflexible conduit extending therebetween is not unduly stressed duringtilt and steering movements of the unit.

References Cited by the Examiner UNITED STATES PATENTS 1,028,333 6/12Desenberg 11542 1,824,213 9/31 Johnson 115-41 1,900,180 3/33 Harvey115-41 2,091,247 8/37 Williams 11541 2,473,618 6/49 Stillwagon 115412,681,029 6/54 Canazzi 115-35 2,718,792 9/55 Kiekhaefer 11534 2,903,9919/59 Carlson et a1. 115.5 3,088,296 5/63 Barker et a1. 115-41 FERGUS s.MIDDLETON, Primary Examiner.

1. IN AN INBOARD-OUTBOARD DRIVE FOR WATERCRAFT, AN ENGINE DISPOSEDINBOARD OF THE WATERCRAFT, A PROPULSION UNIT DISPOSED OUTBOARD OF THEWATERCRAFT AND DIRIGIBLY AND PENDENTLY SUPPORTED THEREFROM FOR STEERINGMOVEMENT ON A GENERALLY VERTICALLY AXIS AND FOR TILT MOVEMENT ON AGENERALLY HORIZONTAL TRANSVERSE AXIS SUBSTANTIALLY INTERSECTING SAIDSTEERING AXIS, A SUBSTANTIALLY VERTICAL DRIVE SHAFT IN SAID PROPULSIONUNIT REARWARD FROM SAID STEERING AXIS, DRIVE MEANS INTERCONNECTING SAIDENGINE AND SAID PROPULSION UNIT DRIVE SHAFT, MOUNTING MEANS FOR SAIDPROPULSION UNIT SECURED TO THE TRANSOM OF THE WATERCRAFT AND SURROUNDINGAN OPENING THROUGH SAID TRANSOM FOR RECEIVING SAID DRIVE MEANS, WATERPICK-UP MEANS IN SAID PROPULSION UNIT, A WATER PUMP IN SAID PROPULSIONUNIT DRIVEN BY SAID DRIVE SHAFT AND CONNECTED TO RECEIVE WATER FROM SAIDPICK-UP MEANS, MEANS TO CONDUCT WATER FROM SAID PUMP THROUGH THEPROPULSION UNIT AND THROUGH THE TRANSOM OPENING AND SAID MOUNTING MEANSTO SAID ENGINE AND INCLUDING FLEXIBLE CONDUIT MEANS ADJACENT SAID AXESINTERSECTION TO PROVIDE FREEDOM FOR STEERING AND TILT MOVEMENTS OF SAIDPROPULSION UNIT UPON SAID AXES.